Volume 7, Issue 5, October 2019, Page: 58-67
Analytical Models for Quark Stars with Van Der Waals Modified Equation of State
Manuel Malaver, Bijective Physics Group, Bijective Physics Institute, Idrija, Slovenia; Department of Basic Sciences, Maritime University of the Caribbean, Catia la Mar, Venezuela
Hamed Daei Kasmaei, Department of Applied Mathematics, Islamic Azad University-Central Tehran Branch, Tehran, Iran
Received: Sep. 7, 2019;       Accepted: Oct. 15, 2019;       Published: Oct. 24, 2019
DOI: 10.11648/j.ijass.20190705.11      View  32      Downloads  8
Abstract
Stellar models consisting of spherically symmetric distribution of charged matter locally anisotropic in strong gravitational fields have been widely considered in the frame of general relativity. These investigations require the generation of exact models through the resolution of the Einstein-Maxwell system of equations. The presence of charge produces values for redshifts, luminosity and mass for the stars different in relation to neutral matter. Some applications for dense charged matter we have them in the description of quark stars, spheres with linear or non-linear equation of state, hybrid stars and accreting process in compact objects where the matter acquires large amounts of electric charge. In this paper, we studied the behavior of relativistic compact objects with anisotropic matter distribution considering Van der Waals modified equation of state proposed in 2013 for Malaver and a gravitational potential Z(x) that depends on an adjustable parameter α in order to integrate analytically the field equations. They generalize the ideal gas law based on plausible reasons that real gases do not act ideally. New exact solutions of the Einstein-Maxwell system are generated and the physical variables as the energy density, radial pressure, mass function, anisotropy factor and the metric functions are written in terms of elementary and polynomial functions. We obtained expressions for radial pressure, density and mass of the stellar object physically acceptable with two different values of the adjustable parameter. The proposed models satisfy all physical features of a realistic star.
Keywords
Relativistic Compact Objects, Gravitational Potential, Einstein-Maxwell System, Radial Pressure, Anisotropy Factor, Matter Distribution, General Relativity, Einstein Field Equations
To cite this article
Manuel Malaver, Hamed Daei Kasmaei, Analytical Models for Quark Stars with Van Der Waals Modified Equation of State, International Journal of Astrophysics and Space Science. Special Issue: Modelling and Simulation of Magnetars and Stellar Objects. Vol. 7, No. 5, 2019, pp. 58-67. doi: 10.11648/j.ijass.20190705.11
Copyright
Copyright © 2019 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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